The invention relates to an air supply arrangement for an internal combustion engine with means for cooling the engine and means for supplying secondary air to the exhaust gas of the engine, particularly for use in motor vehicles.
An internal combustion engine with such an air supply arrangement is shown, for example in U.S. Pat. No. 5,095,591. The arrangement described therein includes an engine fan and an exhaust gas secondary air pump each of which is driven by a hydraulic motor. The hydraulic motors have a common hydraulic fluid supply system which is however only large enough to provide for alternate operation of the hydraulic motors.
U.S. Pat. No. 3,393,668 discloses an exhaust gas catalytic converter in which a secondary air supply pump and an impeller in the catalytic converter are driven by a common electric motor. In that arrangement, the secondary air supply pump and the electric motor form a common structure.
German DOS 1 476 110 discloses an internal combustion engine unit for motor vehicles which includes a central electric motor which operates at constant speed, and drives mechanically several auxiliary units, particularly fluid pumps and an engine cooling fan.
U.S. Pat. No. 4,491,094 discloses a fan for motor vehicle engines which is driven by an electric motor whose motor shaft drives also a vacuum pump for a braking system. Upon operation of the electric motor, the fan as well as the vacuum pump are in operation, the vacuum applied to the pneumatic devices being controllable by means of a pneumatic control element.
It is the object of the present application to provide an internal combustion engine arrangement wherein the engine cooling air and the exhaust gas secondary air supply is realized with particularly simple means.